(a) Field of the Invention
The present invention relates to a polarizer.
(b) Description of the Related Art
Planar lightwave circuit (PLC) technology is technology for fabricating an optical element by forming an optical waveguide serving as an optical communication medium on a planar substrate such as a silicon wafer.
A typical optical waveguide polarizer as an optical waveguide-type optical element is provided with a thin metal line on an optical waveguide to filter an optical signal of a transverse magnetic (TM) mode and pass an optical signal of a transverse electric (TE) mode.
However, such an optical waveguide polarizer exhibits a polarization characteristic, which depends on the wavelength of an optical signal which is in turn dependant on the length, width, and thickness of the metal line.